Well I'm am basing everthing on his question about running faster. For a football player the needs are different depending on the player. Coming off the line in football is different than coming off the blocks. Especially since that power coming off needs to be transferred to a running cadence effeciently. All the power in the world won't do a runner any good if he has a bad start. But again I am talking about the absolute question of RUNNUNG FASTER, where fractions of a second count. There are all sorts of reasons why different considerations may be at play.